Atormac
briv
Neurology India
menu-bar5 Open access journal indexed with Index Medicus
  Users online: 2918  
 Home | Login 
About Editorial board Articlesmenu-bullet NSI Publicationsmenu-bullet Search Instructions Online Submission Subscribe Videos Etcetera Contact
  Navigate Here 
 Search
 
  
 Resource Links
    Similar in PUBMED
    Article in PDF (483 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this Article
   References

 Article Access Statistics
    Viewed920    
    Printed0    
    Emailed0    
    PDF Downloaded19    
    Comments [Add]    

Recommend this journal

 


 
Table of Contents    
COMMENTARY
Year : 2021  |  Volume : 69  |  Issue : 3  |  Page : 628-629

Treatment for Moyamoya Disease: Still a Dilemma?


Sr. Consultant Neurosurgeon, Institute of Neurosciences, Mazumdar Shaw Medical Center, Narayana Health City, Hosur Road, Bangalore, Karnataka, India

Date of Submission02-Jun-2021
Date of Decision02-Jun-2021
Date of Acceptance02-Jun-2021
Date of Web Publication24-Jun-2021

Correspondence Address:
Dr. Shibu V Pillai
Sr. Consultant Neurosurgeon, Institute of Neurosciences, Mazumdar Shaw Medical Center, Narayana Health City, Hosur Road, Bangalore - 560 099, Karnataka
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0028-3886.319245

Rights and Permissions



How to cite this article:
Pillai SV. Treatment for Moyamoya Disease: Still a Dilemma?. Neurol India 2021;69:628-9

How to cite this URL:
Pillai SV. Treatment for Moyamoya Disease: Still a Dilemma?. Neurol India [serial online] 2021 [cited 2021 Jul 24];69:628-9. Available from: https://www.neurologyindia.com/text.asp?2021/69/3/628/319245




I would like to congratulate Gupta, et al., for their recent paper on surgical treatment for moyamoya disease (MD) which has added to the rather sparse literature on this subject among the Indian population.[1]

Moyamoya vasculopathy (MMV) is characterized by progressive stenosis of the supra-clinoid internal carotid artery (ICA) and/or the proximal segments of anterior and middle cerebral arteries. The body fights back by forming a network of new collaterals particularly at the base of the brain to convert the ICA based circulation into an external carotid artery (ECA) based system. Patients with MMV generally present to the hospital with symptoms of chronic cerebral hypoperfusion – transient ischemic attacks (TIAs), stroke, movement disorders, seizures, or cognitive impairment. The longer the duration of chronic hypoperfusion, the greater the severity of cognitive impairment and other symptoms. The newly formed collaterals are responsible for symptoms like hemorrhage and headache. Patients with an early age of onset and a longer duration of MMV prior to treatment are more likely to be functionally challenged compared to those who are diagnosed and treated early.[2]

Medical or conservative therapy has not been standardized and generally consists of antiplatelets, maintenance of hydration and avoidance of hyperventilation. Surgical therapy for MMV attempts to hasten the transition of the cerebral circulation from an ICA to an ECA based system. There are numerous large case series such as the one by Guzman, et al., demonstrating a reduction in symptoms especially reduction in the long-term stroke risk following direct revascularization procedures such as the superficial temporal artery to middle cerebral artery bypass.[3] The main limitation to direct revascularization has been the size of the donor and recipient vessels especially in small children below the age of four years. In my opinion, one of the key messages from this paper by Gupta et al. is that direct/combined revascularization is technically feasible in about 50% of Indian children below the age of five years. Two potential pitfalls of direct/combined revascularization are post-operative ischemia or hemorrhage, and hyper-perfusion syndrome leading to new-onset neurological deficits. Gupta et al. have been able to avoid these devastating complications which can lead to poor long-term outcome.

The natural history of MMV is variable with some patients having a fulminant course whereas others may have a slow progression. Hence, one of the key limitations of this report is the way in which clinical outcome has been reported by clubbing the outcome of 33 patients who had unilateral surgery with those who had bilateral surgery. The fact that this did not make a difference to the outcome suggests that the duration of follow-up was inadequate for such pathology. Although this can be overlooked in light of the rarity of this condition, it does not support the author's conclusion that combined revascularization is the procedure of choice in all patients with MMV.

Mizoi et al. found that a patient's age was inversely proportional to the degree of collateral formation from indirect bypass, and hence, suggested that the direct bypass procedure should be the first-line surgical treatment option for adult MD patients.[4] Gupta et al. did not find any significant difference between the combined and indirect revascularization groups with respect to either regression of moyamoya vessels or the development of good collaterals at the site of revascularization. This once again raises doubts about their recommendation regarding the procedure of choice in MMV.

The only definitive evidence available in the literature regarding treatment of MMV comes from the Japan Adult Moyamoya (JAM) Trial, which was a prospective, randomized, controlled trial designed to evaluate the effectiveness of direct/combined revascularization versus medical management on recurrent bleeding, strokes, and TIA during a 5-year flow-up period among MD patients who present within one year of hemorrhage. Subgroup analysis revealed that this procedure was effective for the treatment of posterior hemorrhages but not for anterior hemorrhages.[5] The result of the 10-year outcome analysis is awaited.

The debate regarding the ideal treatment for ischemic MMV has, on the other hand, been further muddied by several meta-analyses which challenges the benefits of all kinds of revascularization surgery as opposed to medical management alone.[6]

Finally, this paper once again demonstrates the lacunae in the available literature regarding the management of asymptomatic MMV. The Neurological Society of India is perfectly positioned to bring some calm into this perfect storm of confusion by setting up a pan-India registry for such rare disorders as MMV and organizing trials to resolve such management dilemmas in the Indian population.



 
  References Top

1.
Gupta SK, Narayanan R, Aggarwal A, Mohanty M, Ahuja C, Verma N, et al. Outcome Following Surgical Revascularization in Patients of Moyamoya Disease with Focus on Graft Patency and Angiographic Changes. Neurol India 2021;69:620-7.  Back to cited text no. 1
  [Full text]  
2.
Imaizumi T, Hayashi K, Saito K, Osawa M, Fukuyama Y. Long-term outcomes of pediatric moyamoya disease monitored to adulthood. Pediatr Neurol 1998;18:321-5.  Back to cited text no. 2
    
3.
Guzman R, Lee M, Achrol A, Bell-Stephens T, Kelly M, Do HM, et al. Clinical outcome after 450 revascularization procedures for moyamoya disease. J Neurosurg 2009;111:927-35.  Back to cited text no. 3
    
4.
Mizoi K, Kayama T, Yoshimoto T, Nagamine Y. Indirect revascularization for moyamoya disease: Is there a beneficial effect for adult patients? Surg Neurol 1996;45:541-9.  Back to cited text no. 4
    
5.
Takahashi JC, Funaki T, Houkin K, Inoue T, Ogasawara K, Nakagawara J, et al. Significance of the Hemorrhagic Site for Recurrent Bleeding: Prespecified Analysis in the Japan Adult Moyamoya Trial. Stroke 2016;47:37-43.  Back to cited text no. 5
    
6.
Moussouttas M, Rybinnik I. A critical appraisal of bypass surgery in moyamoya disease. Therapeutic Advances in Neurological Disorders. January 2020. doi: 10.1177/1756286420921092.  Back to cited text no. 6
    




 

Top
Print this article  Email this article
   
Online since 20th March '04
Published by Wolters Kluwer - Medknow